[Walsin] Announcement regarding the investor briefing to be held on May 21, 2026

Compliance with Article 4, Paragraph XX: 12

Date of event: 2026/05/21 1. Date of investor briefing: 2026/05/21 2. Time of investor briefing: 14:00 3. Location of investor briefing: No. 30, Kaonan Highway, Renwu District, Kaohsiung City (Conference Room, 2F, Kaonan Plant) 4. Key information: Disclosure of Q1 2026 operational status. 5. Other matters: None.

Please refer to the investor briefing section or list on the Market Observation Post System (MOPS) for comprehensive financial and business information.